Not that you'd expect anything less from Valve and Steam, but it does in fact sound very cool. I'm not a PC gamer by any means, but having a controller that functions like this might make me one. Here's some of the details about the controller, but really if you want more info then check out this page.

The Steam Controller is designed to work with all the games on Steam: past, present, and future. Even the older titles in the catalog and the ones which were not built with controller support. (We’ve fooled those older games into thinking they’re being played with a keyboard and mouse, but we’ve designed a gamepad that’s nothing like either one of those devices.) We think you’ll agree that we’re onto something with the Steam Controller, and now we want your help with the design process.

Traditional gamepads force us to accept compromises. We’ve made it a goal to improve upon the resolution and fidelity of input that’s possible with those devices. The Steam controller offers a new and, we believe, vastly superior control scheme, all while enabling you to play from the comfort of your sofa. Built with high-precision input technologies and focused on low-latency performance, the Steam controller is just what the living-room ordered.